Developing Adaptable Models for Studying Fundamental Properties of Immobilized Enzymes
Abstract
Proteins provide an extraordinary range of structures, properties, and functions that can be exploited for reactive and adaptive systems and materials if the biological molecule can be effectively integrated with standard device technologies. However, there are significant challenges associated with placing a soft solution-phase material (a protein) in contact with hard inorganic substrates, and protein denaturation and and/or loss of function is a significant problem. In addition, current protein-surface integration chemistries lack the ability to ensure uniform orientation relative to the surface or control other important parameters such as the surface density of enzymes. Perhaps worst of all, for most applications, these types of surface functionalization strategies have to be optimized for each individual enzyme and each individual surface, and a particular immobilization method is usually not readily transferable to other systems of interest without significant re-optimization (and often not even then). In this proposal we describe a new modular and highly adaptable approach that addresses all of these shortcomings and that has the potential to generate a wide variety of bio/abio materials where molecular-level control over surface and biological structure leads to control over function. We propose to develop an entirely new and highly adaptable experimental model for enabling reactive and adaptive enzyme function on a wide variety of surfaces and substrates for potential applications in sensing, catalysis, and biocompatible materials. Our goal is to develop a versatile and highly generalizable method for producing sensors and materials that react to specific chemical inputs with productive outputs. Our proposal is centered on enzyme-nanoparticle building blocks that can be easily immobilized on most surfaces, including metals, semiconductors, and plastics, without interfering with enzyme structure, orientation, or activity. We will immobilize enzymes onto gold nanoparticles (AuNPs) using methods developed in our two laboratories. AuNPs will be functionalized with synthetic bifunctional peptides with controlled surface densities and orientations. These peptides will be designed to bind to specific locations on an enzyme surface by maximizing both hydrophobic and hydrophilic noncovalent interactions through peptide sequence. Once the AuNP-peptide-enzyme construct (AuNP-pep-enz) is synthesized, it will be immobilized on any type of substrate surface by coupling directly to the AuNP. This strategy eliminates a significant roadblock in the large field of enzyme surface functionalization: the need to develop new immobilization strategies for each enzyme-surface pair required for a particular application. In other words, the AuNP-pep-enz conjugate is a multi-functional, multi-scale super-molecule that can be synthetically manipulated in orthogonal pieces to generate a functional bio/abio system designed to elicit a wide variety of possible functions. This will be a significant and transformative step toward simplifying biosensor interface design. This proposal represents a new and unfunded collaboration between the laboratories of Dr. Webb, who has developed strong expertise in surface chemistry and protein-surface interactions, and Dr. Crooks, who has long interest in developing novel sensing platforms from nanoscale and hybrid materials. The multidisciplinary collaboration at the interface of biological, surface, and materials science will address a challenging problem beyond the scope of any one field in entirely new and compelling ways.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 14, 2019
- Source ID
- W911NF1710089
Entities
People
- Lauren Webb
Organizations
- Army Contracting Command
- United States Army
- University of Texas at Austin